1. Field of the Invention
The invention relates to a roadway suitable for use in a transportation system and a method for constructing the roadway.
2. Description of the Prior Art
Prior art transportation systems which employed self-propelled, rubber-tired vehicles, such as seen in U.S. Pat. No. 3,312,180 of E. O'Mueller, included aerial and elevated roadways as well as ground-level roadways. An article entitled The Transit Expressway, published by C. Kerr in the January 1963 Westinghouse Engineer at pages 2 to 7, describes such a system. Aerial roadways, supported by columns, were designed to avoid natural and man-made obstacles such as rivers and conventional highways, to provide for cross-overs in the roadway, and to permit horizontal access to buildings at a point significantly above ground level. Elevated roadways, supported at moderate heights by continuous wall structures, were designed for environments subject to flooding or for grade separation of a roadway built over an existing highway. These prior art aerial, elevated, and ground-level roadways consisted of steel and concrete and their construction included the process of pouring concrete into wooden forms which were assembled at the construction site. A typical structure for these roadways and a method for their construction is described in "Transit Expressway Report" and "Transit Expressway Report Phase II" prepared by the MPC Corporation, 4400 5th Avenue, Pittsburgh, Pa. Substantial periods of time were required to construct the forms, pour the concrete, and dismantle the forms after the concrete had dried. This resulted is substantial delay and consequent higher costs in the construction of transportation system. Therefore, there was a need for a roadway which could be constructed quickly and economically.